1. Field of the Invention
The present invention relates to an electronic device. More particularly, the present invention relates to a memory controller in an electronic device.
2. Description of the Related Art
The concept of a processor can be extended to include a Direct Memory Access (DMA) controller that may be regarded as an independent processor. That is, the DMA controller has a right for accessing a memory as a master right.
When data exist inside a memory during data exchange between processors, memory location information and an interrupt signal for the data may be provided to a processor which will receive the data. A representative method includes a mail box method between processors. Here, the mail box method is formed of a message and a hardware interrupt signal (e.g., an except signal).
When the processor or the DMA controller operates, the processor or the DMA controller generates an interrupt signal. That is, an interrupt signal is used as a means for controlling message exchange.
An Interrupt Service software Routine (ISR) reacting to an interrupt signal generated by hardware requires a minimum pre-processing time for context switching, and a delay of about 10 μs˜50 μs is generated due to this pre-processing, depending on an operating system.
However, it is impossible to develop apparatus handler software using a method for processing all these interrupt signals only inside the ISR.
This is because an influence due to the ISR is different depending on a user operation, and because of an Application Programming Interface (API) call that is provided by an operating system when an ISR operates, that is, a system call should be accompanied, which unavoidably generates a delay and has a negative influence on a system performance.
Therefore, a technology for removing an interrupt signal delay is desired.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present invention.